Spotting a Liskov Violation: The Ostrich That Cannot Fly

class Bird:
    def __init__(self, name):
        self.name = name

    def fly(self):
        return f"{self.name} flies south"


class Sparrow(Bird):
    pass


class Ostrich(Bird):
    def fly(self):
        raise NotImplementedError("ostriches cannot fly")


def migrate(birds):
    for bird in birds:
        print(bird.fly())


try:
    migrate([Sparrow("sparrow"), Ostrich("ostrich")])
except NotImplementedError as error:
    print(f"NotImplementedError: {error}")

import java.util.List;

public class LspBirds {
    static void migrate(List<Bird> birds) {
        for (Bird bird : birds) {
            System.out.println(bird.fly());
        }
    }

    public static void main(String[] args) {
        try {
            migrate(List.of(new Sparrow(), new Ostrich()));
        } catch (UnsupportedOperationException error) {
            System.out.println("UnsupportedOperationException: " + error.getMessage());
        }
    }
}

class Bird {
    String fly() {
        return getClass().getSimpleName() + " flies south";
    }
}

class Sparrow extends Bird {}

class Ostrich extends Bird {
    @Override
    String fly() {
        throw new UnsupportedOperationException("ostriches cannot fly");
    }
}

class Bird {
  constructor(readonly name: string) {}

  fly(): string {
    return `${this.name} flies south`;
  }
}

class Sparrow extends Bird {}

class Ostrich extends Bird {
  fly(): string {
    throw new Error("ostriches cannot fly");
  }
}

function migrate(birds: Bird[]): void {
  for (const bird of birds) {
    console.log(bird.fly());
  }
}

try {
  migrate([new Sparrow("sparrow"), new Ostrich("ostrich")]);
} catch (error) {
  console.log(`Error: ${(error as Error).message}`);
}